Treatment of threads and the like



w. l. TAYLOR TREATMENT OF THREADS AND THE LIKE May 4, 1937.

Filed March 28, 1933 WILLIAM I- TAYw R ATTQRNEYS Patented May 4, W3?

TREATMENT OF THREWS AND 'llHE MIKE William Ivan Taylor, Spondon, near Derby, England, assignor to Celanese Corporation of America, a corporation of Delaware Application March 28, 1933, Serial No. 663146 In Great Britain April 14, 1932 12 Claims.

This application is in part a continuation of my application S. No. 393,287 filed Sept. 1'7, 1929 and of'my application S. No. 406,355 which has issued as Patent No. 1,909,192 May 16, 1933.

lZn-the past artificial horse-hair, strips, ribbons and the like have been manufactured from associated artificial filaments by applying softening agent orsolvent thereto so as to cause the substance of the filaments to soften or dissolve in such a way that the individual filaments adhere together and form a large unitary product. The product may have a substantially circular crosssection, or alternativelyit may have a flattened cross-section, such as a strip, the precise cross- 20 section being adjustable in accordance with the shape imparted to the product at the time of causing adherence or at the time of drying. In U. S. application S. No. 393,287 filed 17th September, 1929 processes are described for'the manufacture of this type of product in which a limited quantity of solvent or softening agent is applied to the material, said application being for example by means of a wick, roller, rod or other device moistened with the solvent or softening 3O agent. According to this specification the finalunitary product may still have the appearance of the filamentary products from which it was produced, that is to say the individual filaments constituting an artificial horse-hair for example are still perceptible in the finished product. All i the above products are highly valuable for the construction of fabrics or other materials of a special character, the unitary products constituting either the whole of the fabric or only the warp or weft thereof or being used as effect threads in a fabric consisting mainly of other materials, for instance the threads of ordinary associated filaments.

The present invention relates to an entirely fabrics or other materials containing the same and also to processes for their manufacture. The new thread or associated product of the present invention consists of or comprises a number of artificial filaments which are sumciently adherent to each other (without the aid of a size or other adhesive) to prevent mutual dissociation while the thread is undergoing purely textile op- 55 erations. such as twisting, winding, knitting,

associated filaments.

' new type of thread or associated product and to weaving and the like. Moreover the new thread is characterized by having substantially the same degree of flexibility as that of an ordinary bundle of associated filaments of similar constitution,

and hence the thread can be used in. the manu- 5 facture of ordinary fabrics or fabrics which do not differ in appearance substantially from ordinary fabrics made from threads of associated filaments. By an ordinary bundle of associated filaments of similar constitution is meant a 110 twisted thread containing the same number of filaments of the same composition and denier as form the new type of thread of the present invention. The products of the present invention differ fundamentally from the horse halr type of product in which the filaments are still visible, since, in such products the filaments are firmly adherent together and have to acon'siderable extent merged into one another. In the present products the filaments are only very lightly adhered, and have not merged together, the filaments retaining, therefore, substantially their original structure. The degree of adherence of the individual filaments to each other may be so light as to admit of filaments being drawn tively stifi and is therefore capable of being manufactured to ordinary fabrics .as opposed to efiect fabrics or fabrics which are relatively stiff, yet on the other hand it represents a substantial improvement upon the ordinary dumb thread of ingly difficult to operate with a dumb untwisted thread of associated filaments since the filaments tend to fan and even to break when subjected to light friction. As is well known this dificulty is ordinarily overcome by imparting a twist to ments from fanning during textile operations.

However, the invention is not of course limited to the absence of twist, since in order to imitate absolutely the ordinary thread it may be necessary to impart a small degree of twist. Thus for example the formed thread may be taken up on i In general it is exceeda cap-spinning device, inserting simultaneously a twist of the order of 0.5 to 1.5 turns per inch.

The difiiculty with regard to fanning is more particularly met with in the case of artificial filaments of organic derivatives of cellulose in which friction or other means may set up a high degree of electrification which causes the filaments to repel each other and give rise to the fanning phenomenon. 0n the other hand, fanning may also be encountered with filaments of another character, such as the viscose type of filament, and also these filaments are equally liable to rupture when subjected to light friction in the form of a dumb thread. The thread of the present invention .of the individual filaments without rupture.

whether consisting of the cellulosic type of artificial silk or of the cellulose derivative type eliminates or largely eliminates difiiculties of the above character. The filaments constituting the threads of the present invention are preferably sufficiently adherent to each other to render it completely unnecessary to apply any other agent for the purpose of holding them together. Nevertheless of course it is not outside the scope of the present invention to apply other agents thereto, and particularly lubricants or de-electrifiers, since it is of great advantage to remove electrification even though the individual filaments constituting the thread are sufficiently stuck together to prevent fanning due to mutual repulsion of the individual filaments by electrification, and similarly lubricants may be applied to the threads of the present invention in accordance with the common practice in the art.

The new threads may be produced by any method which enables the individual filaments of an associated bundle of filaments to adhere together in the manner described above, that is v to say sufficiently to prevent fanning but insufiiciently to render the thread stiff and preferably insufilciently to alter substantially the flexibility of the thread or to prevent dissociation In general the most convenient method of producing the product of the present invention is to treat a bundle of associated filaments, preferably in the untwisted state, with a small quantity of solvent or softening agent for the substance of the filaments. Thequantity applied or the concentration in which the solvent or softening agent is applied in an inert or relatively inert medium will be less than that required for the production of the horse-hair type of product produced according to U. S. application S. No. 393,287 filed 17th September, 1929, and less even than that required to produce even the horse-hair ty of product in which the individual filaments which have made up the horse-hair are still clearly visible.

The solvent or softening agent may be applied by any suitable method which enables a limited quantity to be distributed upon the bundle of filaments. .It may for instance be applied as a very dilute solution in an inert diluent, or alternatively only small quantities of a solution in a diluent may be applied, in which case higher concentrations of the solvent or softening agent may be used. Ingeneral I prefer to employ the methods of applying small quantities of liquor specifically described in U. S. applications. No. 393,287 filed 17th September, 1929 namely applying the solvent or softening agent by means of wicks, rollers, rods or other devices moistened with the requisite quantity. A spray may likewhe be used for applying the desired small natively, the solvent or softening agent may be applied to the filaments in the vapor form, and in this case the filaments may be led through a chamber containing the vapor of the solvent or softening agent together if desired with inert diluent, and simultaneously or subsequently brought into contact with one another. By controlling the temperature of the softening chamber and the temperature of the filaments, a controlled amount of solvent or softening agent may be caused to condense on the surface of the filaments.

While relatively volatile solvents, such as ace- 9 tone, acetone and alcohol or methylene ethylene dioxide for acetone-soluble cellulose acetate, may be employed in accordance with the present invention, I prefer when the solvents or softening agents are to be applied from a wick or similar device to use solvents or softening agents which are less volatile or relatively non-volatile, since this eliminates difllculties due to evaporation from the wick or other device by means of which the solvent or softening agent is applied. In the case of cellulose acetate and most of the organic derivatives of cellulose, dioxane and its homologues orsubstitution products or other cyclic ethers of low volatility, dioxydioxanes and their ethers and esters, triacetin, diacetin, ethyl lactate, diacetone alcohol, glycol mono-acetate, methyl glycol mono-acetate, ethyl hydroxy-isobutyrate,

methyl ethylene glycol, ethyl diethylene glycol mono-acetate, cyclo-hexanyl acetate, cyclohexanone, benzyl alcohol and butyrone may be used, and with the cellulosic type of artificial silk, Schweitzer's reagent, sulphuric acid or zinc chloride may be used. Again, mixtures of liquids having a solvent or restricted solvent action may be employed, e. g. methyl or ethyl alcohol with methylene or ethylene chloride or with ethyl acetate. As already indicated, the invention is of greatest advantage when applied to the treatment of materials made of or containing organic derivatives of cellulose, since not only are these materials more particularly subject to the dimculties previously referred to, but in addition the number of solvents or softening agents available for these materials is very large. It is impossible to leave Schweitzer's reagent, zinc chloride or sulphuric acid permanently in cellulosic materials, and hence they have to be removed, whereas in the case of the organic derivatives of cellulose the solvent or softening agent may be chosen so that it has no deleterious effect upon the materials, and owing to the small quantity applied in accordance with the present invention it may safely be allowed to stay in.

The solvent or softening agent is preferably applied in conjunction with an inert or relatively inert diluent, though as previously indicated a spray forms one means of applying the small quantities of solvents or softening agent demanded by the present invention without the aid of a diluent. Suitable diluents are water, alcohols, e. g. methyl, ethyl and propyl alcohol, ethers, and particularly the less volatile ethers, e. g. isopropyl ether; esters, e. g. ethyl acetate and propyl acetate; and the hydrocarbons of the aliphatic, aromatic or hydroaromatic series. If a lubricating oil is to be applied to the filaments for the purpose of lubricating them for any particular textile operation, such as knitting, then it is very convenient in accordance with the present invention to apply the small quantity of solvent or softening agent in conjunction with or in solution in such medium. Similarly if a de-elec-,

trifier or any other agent is to be applied to the materials then such other agents may be applied either together with or separately from the solvent or softening agent of the present invention.

, It is most convenient to apply de-ele'ctrifiers or other reagents together with the solvent or softening-agent of the invention if they are comdroxy groups, as for example ethanolamine oleate and other ethanolamine soaps or oleates or other soaps of other amino alcohols; other alcoholic bodies in general, as for example glycerine and derivatives of glycerine and the higher alcohols obtainable by chlorination of paraflin hydrocarbons followed by substitution of the chlorine by a hydroxy group; and amino'alkylamines of fatty acids, and particularly higher fatty acids, for instance the mono-oleyl-ethylene-diamine. Some of the above agents are de-electrifiers, some are lubricants and some act in both capacities. It is as already stated highly convenient in accordance with the present invention to apply a de-electrifier and/or a lubricant together with the solvent or softening agent, and in fact the de-electrifier or lubricant may be the means of reducing the concentration of the solvent or softening agent so that only a relatively small quantity is applied to any part of the filaments; and in consequence the degree of adherence is low.

The concentration of the solvent orsoftening agent will of course vary with the particular solvent or softener and diluent chosen. Thus,

for instance, where filaments of acetone-soluble cellulose acetate are treated continuously with their production by the dry spinning method, glycol monoacetate may be applied very conveniently in a concentration of about 2 to 3% in a paraffin hydrocarbon, while if ethyl acetate, which has some action upon this cellulose. acetate,

be employed as diluent then such concentration will in most cases yield the horse-hair type of product, so that glycol monoacetate with ethyl acetate as diluent will have to be employed, in a much lower concentration for use in the-present invention, e. g. in a concentration of 0.05 to 0.10% up to 0.20%. When the process is applied 'to yarn that has been dried, as distinct from concentration of solvent will be used than if only 50 or of the mixture be applied. The

amount of solvent or softening agent applied,

moreover, will vary with a number of factors, e. g. the denier and the filament denier of the yarn being treated and the degree of hardness or softness which it is desired to obtain in the finished product. Again, where the solvent or softening agent is applied from a wick the size of the wickand the height of the wick above the level of the liquid will be material factors in determining the concentration of the solvent or softening agent in the diluent. In general, however, it appears that proportions of solvent of about .1 to .3% of the weight of the materials should be used, though this will of course depend upon the strength of the solvent and other factors., I have foundtliat it is of advantage to apply to the material a mixture of paramn hy drocarbon containing2 to 3% of glycol monoacetate and about 20% of an ethanolamine soap as de-electrifler and lubricant.

The operation of causing slight adherence of the individual filaments of a bundle of filaments in accordance with the present invention may be applied to the materials at any suitable stage of their manufacture, for example while they a are travelling from bobbin to bobbin, for instance in a re-winding operation, or from bobbin to pirn or cone or any other re-winding operation, in a beaming operation or in a sizing operation, or to any other process in which the filaments are travelling from point to point. The process of the present invention may be applied moreover to the materials, preferably dry, continuously'with their manufacture. Thus for instance a wick or other device may be mounted in front of or on a spinning machine and especially a spinning machine employing the dry or evaporative method, and

the filaments directed from the spinning machine or from a feed roller used in conjunction therewith may be carried over orotherwise in contact with the wick so as to take up the requisite amount of solvent. After treatment the filaments may be wound or twisted and wound as desired, and reference is, made broadly to the description in U. S. application S. No. 393,287 filed l'lth September, 1929. The process of the present invention may be carried out under carefully controlled conditions of temperature and ,humidity, e. g. by enclosing the wick or other apparatus in a chamber wherein the desired conditions can be maintained. Such precautions are not essential and it is found, in fact, that they are less/necessary than when thehorse-hair or semi-coalesced type of product of U. S. application S. No. 393,287 filed 17th September, 1929 is to be produced. However it is desirable to carry out the operation under conditions in which the relative humidity is comparatively low.

As already indicated it is not necessary to remove the solvent or softening agent from materials consisting of organic derivatives of cellulose, since the small amount of solvent or softening agent applied in accordance with the present invention may well be allowed to remain in the materials. Nevertheless where the solvent or softening agent is applied in a diluent which it is not desired to retain u on t e materials, then such diluent may be re ve whether or not the solvent or softening a it removed. Thus, for instance, if a I latively non-volatile solvent or softening agent b applied'in a volatile solvent, such as an ether or a volatile petroleum hydrocarbon, then the diluent may he removed by simple evaporation. Evaporation may be accelerated by application'of heat or more conveniently it is accelerated by whizzing the materials as for example in the ballooning operation in cap spinning or ring spinning.

It is not essential in accordance with the present invention that the individual filaments shall be lightly stuck together throughout their entire length, since it is sufficient in order to prevent fanning or to overcome difiiculties due to rupture of individual filaments to cause the filaments of a bundle of filaments to be lightly adherent intermittently along their length. The product will then be constituted by a bundle in which at intervals, preferably very close, along its length all eifects. Thus, for instance, instead of causing the bundle of lightly adherent filaments to assume a roughly circular crosssection, they may be caused to assume any other desired configuration, for example a more or less flattened crosssection. This may be done by arranging the filaments in a suitable manner before, at the same time or just after applying the solvent or softening agent. Again, the individual filaments of two or more bundles of filaments or two or more portions of a bundle of filaments may be lightly stuck together in accordance with the present invention and then the bundles may be lightly stuck to each other so as to produce a product of more or less flattened cross-section. Such a product may be used in the untwisted state in a fabric so as to give the appearance of two wefts,-for example, ,in a single shed. In addition the threads of the present invention may be used for any other desired purpose, as for example for the manufacture of crepe threads, that is to say threads of very high twist, for example of the order of 50 to 70 turns per inch, and woven into a crepe fabric.

The invention has been described above with reference to any type of filament, but it has been indicated that it is more particularly of value in connection with materials made of or containing cellulose acetate or other organic derivatives of cellulose. Further examples of such organic derivatives of cellulose are cellulose formate, propionate and butyrate, nitro-acetate or other organic esters or mixed esters ofcellulose and ethyl and benzyl celluloses, and other cellulose ethers or mixed ethers or mixed ether-esters.

The accompanying drawing illustrates suitable apparatus for carrying out the process of the present invention but it is to be understood that the invention is not limited thereto.

Figure 1 illustrates in side elevation one form of apparatus for carrying out the process of the present invention continuously with dry spinning the filaments.

Figure 2 illustrates 'diagramatieally a crosssection of the lightly adhered thread produced according to the processes of this invention.

According to Figure 1 a bundle of filaments l issuing from a dry spinning metier 2 are led over a feed roller 3 and thence over a wick 4 partial 1y immersed in a softening liquid 5 contained in a vessel 6. The vessel 6 is provided with a cover I to reduce evaporation of the softenting agent,

and the cover I is provided with a slot allowing passage of the filaments. The vessel 8 is also provided with a device enabling it to be replenished with liquid, such as the filling tube 8. After passing the wick 4 the bundle of filaments is led to a cap-spinning device 9.

A cross-section of a thread produced is illustrated diagrammatically in Figure 2, where it is shown that the filaments produced by this invention do not lose their identity during'the process but are only lightly adhered at their contacting surfaces.

The following examples illustrate the invention but are not to be considered as in any way limiting it.

Example 1 A 23-25% solution of cellulose acetate in aceof their weight of the softening agent. Af-

ter passing the wick the solvent and diluenton the filaments are allowed to evaporate and the bundle of filaments now lightly adhering to one another is led on to a winding device or if desired to a winding and twisting device in which a low twist is imparted.

Example 2 The operations described in Example 1 are carried out employing as softening liquid, a solution of 0.5-1% of ethyl alcohol in ethyl acetate. A

thread consisting of lightly adhered filaments is produced.

Example 3 A bundle of untwisted filaments is led from a bobbin over a wick or similar device adapted to apply liquid to the filaments. By means of this device a solution of 0.20-0.25% glycol monoacetate in ethyl acetate is applied to the filaments, which are thus caused to adhere lightly to each other. The thread may be wound without twisting or may be taken up on a cap spinning device adapted to insert a twist of about 0.5 turns per inch into the thread.

What I claim and desire to secure by Letters Patent is: 1

1. Process for the production of a thread, which comprises applying to a plurality of continuous contacting filaments a solvent medium in sufficient amount and concentration to render tacky the substance of the filaments but insufllcient in amount and concentration to cause coales-' 1 cence of the individual filaments, thereby causing the contacting filaments to adhere to one another and, when no longer tacky, to remain adherent 'but capable of separation from one another, the

thread having a flexibility substantially equal to a normal bundle of filaments of similar constitution.

2. Process for the production of a thread, which comprises applying to a plurality of continuous contacting filaments having a basis of an organic derivative of cellulose a solvent medium in sufiicient amount and concentration to render tacky the substance of the filaments but insufficient in amount and concentration to cause coalescence of the individual filaments, thereby causing the thread having a fiexibility substantially equal to a normal bundle of filaments of similar constitution.

3. Process for the production of a thread, which comprises applying to a plurality of continuous contacting filaments having a basis of cellulose acetate a solvent medium in sufiicient amount and concentration to render tacky the substance of the filaments but insufiicient in amount and concentration to cause coalescence of the individual filaments, thereby causing the contacting filaments to adhere to one anotherand, when no longer tacky, to remain adherent but capable of separation from one another, the thread having a flexibility substantially equal to a normal bundle of filaments of similar constitution.

4. Process for the production of a thread, which comprises applying to a plurality of continuous contacting filaments having a basis of cellulose acetate a dilute solution in an inert medium of a solvent for cellulose acetate in sufficient amount and concentration to render tacky the substance of the filaments but insufiicient in amount and concentration to cause coalescence of the individual fiiaments, thereby causing the contacting filaments to adhere to one another and, when no longer tacky, to remain adherent but capable of the contacting filaments to adhere to one another a and, when no longer tacky, to remain adherent but capable of separation from one another, the thread havinga flexibility substantially equal to a normal bundle, of filaments of similar constitu tion. I

6. Process for the production of a thread, which comprises applying to a plurality of continuous filaments having a basis of cellulose acetate a 2 to 3% solution in an inert medium of a solvent for cellulose acetate, the amount of solvent applied being about 0.1 to 0.3% of the weight of the filaments, whichsolution temporarily ren-' ders tacky the substance of the filaments and causes associated filaments to adhere to one another so'that individual filaments suflfer no alteratiou in cross-sectional form and, when no longer tacky, remain adherent but are capable of separation from one anothen'the thread having a flexibility substantially, equal to a normal bundle oi filaments of similar constitution.

7. Process for the production of a thread, which comprises applying to a plurality of continuous contacting filaments having a basis of cellulose acetate a 0.05 to 0.3% solution of glycol mono- .acetate .inethyl acetate, in sufiicient amount to render tacky the substance of the filaments but insufiicient in amount to cause coalescence of the individual filaments, thereby causing the contacting filaments to adhere to one another and,

when no longer tacky, to remain adherent but capable of separation from one another, the,

thread having a flexibility substantially equal to a normal bundle of filaments of similar constitution.

8. Process for the production of a thread, which. comprises applying to a plurality of continuousfilaments having a basis of cellulose acetate a:

0.05 to 0.3% solution of glycol monoacetate in ethyl acetate, the amount of glycol mono-acetate applied being about 0.1 to 0.3% of, the weight of the filaments, which solution temporarily renders tacky the substance of the filaments and causes associated filaments to adhere to one another so that individual filaments sufler no alteration in cross-sectional form and, when no longer tacky, remain adherent but are capable of separation from one another, the thread having a flexibility substantially equal to a. normal bundle of filaments of similar constitution.

9. Process for the production of a thread, which comprises applying, in an atmosphere having a low relative humidity, to a plurality of continuous filaments having a basis of cellulose acetate 2. 0.05 to 0.3% solution of glycol mono-acetate in their length by their own substance but retainin filamentary cross-sections and capable of separation from oneanother, the threads having a flex ibility substantially equal to that of a normal bundle of filaments. 11. Threads comprising a plurality of continuous filaments having a basis of an organic derivative of cellulose, said filaments being united along their length by their own substance but retaining filamentary cross-sections and capable of separation from one another, the threads having a fiexilibity substantially equal to that of a normal bundle of filaments,

12. Threads comprising a plurality of continuous filaments having a basis of cellulose acetate,

said filaments being united along their length by their own substance but retaining filamentary cross-sections and capable of separation from one another, the threads having a flexibility substantially equal to that of a normal bundle of filaments.

' WILLIAM IVAN TAYLOR. 

